Fluid filters are designed to remove solid or other impurities from a fluid (liquid and/or gas) by means of a porous physical barrier. The physical barrier is often referred to as the “filter medium”. Many types of filter media exist. Some filter media are compressible, allowing an adjustment of the size and/or shape of their pores, thereby enabling the removal of impurities of different sizes and/or shapes. Other filter media remove impurities by means of interception and causing adherence of the particles, requiring water to flow flows at a relatively slow rate.
In addition to their filtering mode of operation, fluid filters are often also configured to be operated in a washing mode. In the washing mode, a fluid is streamed in the opposite direction to the filtering direction, thereby washing away the impurities previously caught in the filter medium. In some cases, the media may be expanded before or during the washing, thereby allowing the caught impurities to escape from the pores into the washing fluid.
One common type of fluid filters is a water filter. Water filters are used, for example, in water treatment plants, desalination plants, and points-of-use, such as residential or commercial sites. These filters may filter water intended for drinking, irrigation and/or industrial purposes, removing impurities ranging from dirt to pathogens.
The foregoing examples of the related art and limitations related therewith are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the figures.